The US will send an additional 1,400 Marines to Afghanistan in anticipation of intensified fighting in the spring as winter snow melts and fighters return form havens in Pakistan. The unexpected announcement came as the British defense secretary said that anticipated British troop pullouts this year were not a guarantee.

Military officials worry that an increase in attacks in the spring could be seen as a result of a flawed strategy – the troop increase – and would make US lawmakers want to speed up the troop pullout, the Wall Street Journal reports.

The Journal notes that the additional 1,400 Marines could bring the total troop surge beyond the 30,000 announced by President Barack Obama in December 2009. At the time, he authorized Secretary Gates to up forces by an additional 10 percent (3,000) in the case of unforeseen circumstances, and officials estimate that 2,000 to 3,000 of those slots have already been used.

"The rationale is to take advantage of the gains we have made over the last several months and apply more pressure on the enemy at a time when he is already under the gun," Pentagon Press Secretary Geoff Morrell told the Journal.

In a related announcement, UK Defense Secretary Liam Fox said in Kabul yesterday that anticipated withdrawals among British troops would depend on ground conditions. Britons had been hopeful for a troop reduction when Prime Minister David Cameron announced after a a December visit to Afghanistan that bringing troops home in 2011 was “possible,” a second Journal report notes.

“Conditions have improved but we will want to ensure that that progress has been maintained and we will want to make sure that the training mission for Afghanistan is fully up to speed,” Defense Secretary Fox said Wednesday in Kabul.

The US has nearly 100,000 troops in Afghanistan now, and the UK has the second-largest contingent – about 10,000.

Fox added, however, that the role for British troops may change this year to focus on training Afghan security. Afghan forces are slated to take over responsibility from foreign troops in 2014, according to the first Journal report.

The US and its NATO allies are spending record amounts on equipping Afghan forces. As the Washington Post reports, they plan to spend $11.6 billion on Afghan forces this year, bringing the total to nearly $20 billion for 2010 and 2011 – as high as all seven previous years combined.